Neural predictors of purchases

Abstract

Microeconomic theory maintains that purchases are driven by a combination of consumer preference and price. Using event-related fMRI, we investigated how people weigh these factors to make purchasing decisions. Consistent with neuroimaging evidence suggesting that distinct circuits anticipate gain and loss, product preference activated the nucleus accumbens (NAcc), while excessive prices activated the insula and deactivated the mesial prefrontal cortex (MPFC) prior to the purchase decision. Activity from each of these regions independently predicted immediately subsequent purchases above and beyond self-report variables. These findings suggest that activation of distinct neural circuits related to anticipatory affect precedes and supports consumers' purchasing decisions.

Figures

Figure 1

SHOP task trial structure and regressors. For task structure, subjects saw a labeled product (product period; 4 s), saw the product’s price (price period; 4 s), and then chose either to purchase the product or not (by selecting either “yes” or “no” presented randomly on the right or left side of the screen; choice period; 4 s), before fixating on a crosshair (2 s) prior to the onset of the next trial. In regression models, preference was correlated with brain activation during the product and price periods, price differential was correlated with brain activation during the price period, and purchasing was correlated with brain activation during the choice period.

Figure 2

Correlated activation, volumes of interest, and corresponding activation time-courses. Top row (L-R): Conjoined correlations of NAcc activation with preference during product and price periods; MPFC activation with price differential during the price period; and insula activation with decision not to purchase during the choice period (n=26). Middle row (L-R): Volumes of interest superimposed on structural images of the bilateral NAcc, bilateral MPFC, and right insula. Bottom row (L-R): Bilateral NAcc activation time-courses for trials in which products were subsequently purchased versus not; bilateral MPFC activation time-courses; right insula activation time-courses (white=predicted divergence, ***=product period, $$$=price period, ???=choice period, all lagged / shifted right by 4 s; n=26, *p<.05>